28 



HYMENOPTERA. 



70. Thynnus (Agriomyia) vigilans. B.M. 



Male. Length 8 lines. — Black, and thinly covered with cine- 

 reous pubescence, which is most dense on the body beneath and 

 on the metathorax ; the mandibles, margins of the face on each 

 side of the clypeus, a narrow line on the lower portion of the 

 orbits of the eyes, and a narrow stripe on each side of the hinder 

 margin of the vertex, yellow. Thorax : a minute yellow spot on 

 the scutellum and post-scutellum ; wings hyaline, the nervines 

 fusro-ferruginous. Abdomen finely punctured; the margins of 

 the segments slightly constricted; a subovate yellow spot on 

 each side of the four basal segments. 



Hab. Australia. 



71. Thynnus cognatus. B.M. 



Male. Length 6 lines. — Black : the head, thorax, and abdo- 

 men beneath covered with long griseous pubescence ; the abdo- 

 men has a thin short cinereous pubescence above. Head and 

 thorax covered with confluent punctures ; the anterior margins 

 of the face and clypeus and the mandibles yellow ; the tarsi 

 and articulations of the legs ferruginous, the tarsi slightly fus- 

 cous above ; wings fulvo-hyaline, the nervures fusco-ferruginous. 

 Abdomen subpetiolate, smooth, and shining ; the four basal seg- 

 ments with an ovate orange spot on each side'. 



Hab. Australia. 



This species is similarly coloured to T. vigilans, but differs in 

 having the anterior margin of the clypeus yellow, the tarsi of a 

 different colour, and in having the abdomen subpetiolate, shining, 

 and not punctured. 



72. Thynnus Xanthorrhoei (MS. MacLeay). B.M. 



Male. Length 6 lines. — Black : the mandibles, labrum, inner 

 and outer orbits of the eyes interrupted at their summit, a 

 minute spot on the hinder margin of the vertex, and an elongate 

 one between the antennae which is divided by a narrow black 

 line, yellow. Thorax : the margins of the prothorax, three large 

 irregular-shaped spots beneath the wings, two pointed stripes on 

 the mesothorax, an angular spot on the scutellum and a spot 

 on each side, the post-scutellum with a spot on each side, and 

 the metathorax, yellow ; a central longitudinal black line and a 

 large black spot on each side of the metathorax ; the legs ferru- 

 ginous, with the coxa3 yellow ; the trochanters black, and the 

 apical joints of the tarsi fuscous ; wiDgs hyaline, the nervures 

 fusco-ferruginous. Abdomen : all the segments, excepting the 

 apical one, with a transverse yellow fascia in the middle more 



